Water flows into a tank at the rate of 55 ℓ per minute. After 22 min, the tap is turned off and the tank is 0.4 filled with water.
- How much more water is needed to fill it to the brim?
- The water in the tank is then poured into containers each 1.5 m long, 0.5 m wide and 22 cm high. What is the minimum number of containers needed?
(a)
0.4 =
25 Let 5 u be the total volume of water when the tank is completely filled.
Volume of water in the tank
= 55 x 22
= 1210 ℓ
2 u = 1210
1 u = 1210 ÷ 2 = 605
Volume of water to fill the tank to the brim
= 5 u - 2 u
= 3 u
= 3 x 605
= 1815 ℓ
(b)
1 m = 100 cm
1.5 m = 150 cm
0.5 m = 50 cm
Volume of each container
= 150 x 50 x 22
= 165000 cm
3 Volume of water in the tank = 1210 ℓ
1 ℓ = 1000 mℓ
1210 ℓ = 1210000 mℓ
Number of containers needed
= 1210000 ÷ 165000
= 7 r 55000
Minimum number of containers needed
= 7 + 1
= 8
Answer(s): (a) 1815 ℓ; (b) 8